Apparatus for the amalgamation



June 2, 1936. c. J. F. PHILY DlT DE PHIL 2,043,115

APPARATUS FOR THE AMALGAMATION OF ORES Filed July 26, 1954 V Invrzfor:GSIRP/zf? at deP/ 'g,

Patented June 2, 1936 UNITED STATES PATENT OFFICE ORES Claude JosephFrancois Phily, dit de Phily, Le Genest, France Application July 26,1934, Serial No. 737,078 In France March 19, 1934 9 Claims.

The present invention concerns an apparatus particularly intended forthe extraction of amalgamable metals, such as gold, contained in ores,said extraction being obtained even without the usual assistance ofwater and with a higher efficiency than with the processes hithertoknown.

Apparatus may consequently be used for the extraction of metals existingat a free state into ores, which are previously crushed when necessaryand both process and apparatus may also be used for the collection ofany amalgamable silver contained into roasted ores or in any other casein which amalgamation may be used.

The main feature of the present invention con- 5 sists in utilizing, inorder to obtain the amalgamation, the surface tension or surfaceviscosity phenomena well known in physics under the name of Pasteurstests. Should the surface of a bath of mercury be covered with finesandstone 20 and a rod be vertically dipped into the bath, the

sand will disappear as if it was drawn by the rod, and will subsequentlyreturn at the surface upon removal of the rod.

I have ascertained that whatever may be the thickness of the layer offine sand covering the mercury, the thickness of sand drawn by the rodremains at the least value corresponding to the size of its grains, andis continuous as long as the rod sinks and as sand is left upon thesurface. 30 According to the invention the main feature of the apparatusintended to carry out the present process is constituted by elements towhich is imparted a continuous motion, such as sheet metals forinstance, the superficial extension of which 35 is as large as possible.Such elements dip into a bath of mercury, thus drawing the sandaccording to the surface viscosity or surface tension phenomenamentioned above.

An arrangement which is particularly advanta- 40 geous is as follows:the entrainment of the sand' ore is produced by the rotary motion aroundtheir axis of one or more cylinders provided with flat blades placedperpendicularly with respect to the axis of the cylinder and sunk up toa given depth 45 into a bath of mercury: the sand is poured at thesurface of the mercury from one side of the cylinder, and is drawn intothe mercury by means of the blades which carry it under the cylinder;the sand comes up again at the surface at the other 50 side, after beingexhausted.

According to a further feature of the invention, the rotary motionimparted to the cylinder should be slow: the blades being rotary bodies,in such case there is no stirring of the mass. I have 55 ascertainedthat in such conditions the amalgam which is richer in gold accumulatesat the base of the container, separation taking place by gravity.

It will be advantageous to place the one after the other two or moreexhaustion cylinders.

The metal which would not come into contact with the mercury, owing tothe arrangement of the grains of sand, during the passage under thefirst cylinder, will be recovered in the subsequent ones. 10

In order to reduce the amount of mercury used, it will be advantageousto design the tank containing the bath in the form of a half-cylinderconcentrical to the blade carrying cylinder; at the bottom of said tankis provided a discharge cock enabling the continuous or discontinuousextraction of the rich amalgam thus formed.

In order that the invention may be fully understood, it will be nowdescribed with reference to the accompanying drawing in which:

Figure 1 is a diagrammatic sectional view of an apparatus according tothe present invention.

Figure 2 is a diagrammatic view in horizontal section corresponding tothe line II-II of Figure 1.

Figure 3 is a diagrammatic view in vertical axial section of anapparatus provided with two elements in series, according to theinvention.

Figure 4 is a diagrammatic view of a threeelements apparatus accordingto the invention.

The apparatus shown in Figures 1 and 2 is constituted by an ironcylinder I whose lateral surface is provided with blades 2 of iron orlike material resistant mercury, such as aluminium, wood, glass or thelike. into planes which are perpendicular to the axis of the cylinder,the said arrangement providing a large area of contact for relativelyreduced overall dimensions of the cylinder.

The blade carrying cylinder l revolves slowly 40 and in a continuousdirection around its fixed horizontal axis, in a semi-cylindrical trough3 filled with mercury.

The inlet zone of the blades into the mercury is supplied with oresieved through fine meshes.

The grains entrained by the blades or sticking to them owing to surfacetension are automatically released at the discharge end of the device,as' soon as immersion is finished, and since they accumulate in thisplace they soon overflow, upon i a weir 4. During the immersion theyleave their amalgamable particles into the bath.

The easy recovery of the dissolved gold is based upon the principlewhich has been acknowledged by the inventor that a liquid alloy of twometals Said blades are arranged 35 1 of sufliciently differentdensities, such as mercury and gold and of contents which are still farfrom the value corresponding to their solid alloy at the temperature ofthe bath, tends to concentrate in state of rest into the part whichfacilitates the production of a solid solution, either for the systemmercury-gold at the lower part or for the system mercury-silver at thesurface.

The gold amalgamating apparatus is consequently provided at the bottomof the trough, with an adjustable opening 5 for the discharge of theauriferous mercury. The discharge performs continuously drop after drop,in order to avoid that a too long period of rest, may allow theconcentration to take place up to a solid solution content (about 45 percent gold), thus obstructing the opening 5 (in the silver amalgamatingapparatus a similar device is provided adjacent to the free surface).

The mercury thus removed is replaced at regular periods of time, byfresh mercury which is added in the trough 3. The amount of mercuryadded will be higher than the amount discharged through the opening 5.The excess of fresh mercury will cause a discharge of the soiled mercuryrising at the surface, by means of an overflow (not shown). Thisdischarge from the surface permits the renewal of the active surface ofthe mercury and the collection of the light amalgams such as that ofsilver.

The liquid amalgam thus collected is either once more concentrated bysedimentation, in order to be subsequently treated by means of a chamoisleather or directly subjected to said treatment.

The amalgam is clean since being collected far from its surface, itcannot contain any of the usual impurities, sand or pyrites which are sodifiicult to eliminate when collection is accomplished upon the usualamalgamation tables.

The apparatus may be constituted by a single unit consisting of acylinder-trough or as shown in Figure 3, by two or three elements inseries, each of the subsequent element collecting in its turn, for itsentrainment, the sand delivered by the preceding one. For some ores ofthe gauge of sands the arrangement in series is liable to increase theefficiency by increasing the period of immersion and changing from oneelement to another the arrangement of the entrained layers.

Though this is not generally necessary, it is possible to activate theamalgamation of some ores by leading an electric current through thebath or by the addition of an activating agent, such as sodium.

The process may be used either as a dry process or as a wet process,provided that in both cases the fluidity or easy displacement of thesolid particles the ones with respect to the others, is secured fortheir entrainment. The intermediate state, i. e. a given amount ofhumidity which would agglomerate the sand to be treated would alsoprevent entrainment.

The advantage of the dry process is that a higher output is required forequal size of apparatus, the action of surface tension being morepowerful. The advantage of the wet process is that a minor amount ofmercury is entrained in the sand being discharged. The choice of theprocess will depend upon local conditions.

In the case of the wet process an advantageous arrangement consists topartially or totally drown with water the apparatus above the surface ofthe mercury. The immersion into water of the upper part of the rotarysurface has two advantages, i. e. first to secure in a constant manner asufiicient dilution of the pulp in the inlet zones and second toaccomplish a permanent cleaning of the revolving surface. The sands fallinto a chamber which is also submerged with water and are then carriedto the separator by means of a paternoster 6. Figure 4 shows a wateramalgamating apparatus, with three cylinders provided with interleavedblades.

Before being finally discarded, the discharged sands are carried to adry or wet separator in order to recover the mercury which they maycontain. The mercury thus recovered may continuously be brought back tothe apparatus.

The advantages of an apparatus of the above mentioned type are thefollowing: first that it is possible to treat auriferous ores in regionsdeprived from water, second to supply a higher efiiciency ofamalgamation compared to the usual wet processes, due to the directcontact between gold and mercury and owing to the fact that there is noloss of the finest particles entrained as floating gold in the usualtreatments with water current.

Further, the gold amalgam thus obtained is clean and the strivingwashing operations are dispensed with. The gold and silver amalgams arethus recovered separately and thus are not mixed, as in the case of themethods now in use.

The operation is continuous and necessitates no stopping for collectingor cleaning; it enables to reduce labor costs.

The overall dimensions are considerably reduced for the same output.

Finally the precautions against thefts are easier, the amalgam beingcollected only in one place for the whole factory.

Having now particularly described and ascertained the nature of myinvention and in what manner the same is to be performed, I declare thatwhat I claim is:

1. Apparatus for extracting precious metals from ores in a container byamalgamation, comprising at least one trough filled with mercury, ashaft, means for rotating said shaft continuously, a drum mounted onsaid shaft so as to be partially immersed in the mercury bath, bladesfixed on said drum and disposed in planes perpendicular to the axis ofsaid drum, the said drum and the said blades being formed of a materialwhich is not wetted by mercury, and means for feeding the ores betweenthe drum, the blades, and the trough from the side of the drum, and theblades penetrating into the mercury bath.

2. Apparatus for extracting precious metals from ores in a container byamalgamation, comprising at least one trough filled with mercury, ashaft, means for rotating said shaft continuously, a drum mounted onsaid shaft so as to be partially immersed in the mercury bath, bladesfixed on said drum and disposed in planes perpendicular to the axis ofsaid drum, the said drum and the said blades being formed of a materialwhich is not wetted by mercury, means for feeding the ores between thedrum, the blades, and the trough from the side of the drum, and theblades penetrating into the mercury bath, and a weir disposed at theside of the drum opposite to said feeding means, the blades leaving themercury bath adjacent said weir and evacuating the spent ores from saidbath onto said weir.

3. Apparatus for extracting precious metals from ores in a container byamalgamation, comprising at least one trough filled with mercury, ashaft, means for rotating said shaft continuously,

a drum mounted on said shaft so as to be partially immersed in themercury bath, blades fixed on said drum and disposed in planesperpendicular to the axis of said drum, the said drum and the saidblades being formed of a material which is not wetted by mercury, meansfor feeding the ores between the drum, the blades, and the trough fromthe side of the drum, and the blades penetrating into the mercury bath,and means disposed at the bottom of the trough for evacuating whatevergold amalgam is formed.

4. Apparatus for extracting precious metals from ores in a container byamalgamation, comprising at least one trough filled with mercury, ashaft, means for rotating said shaft continuously, a drum mounted onsaid shaft so as to be partially immersed in the mercury bath, bladesfixed on said drum and disposed in planes perpendicular to the axis ofsaid drum, the said drum and the said blades being formed of a materialwhich is not wetted by mercury, means for feeding the ores between thedrum, the blades, and the trough from the side of the drum, and theblades penetrating into the mercury bath, means at the lowest point insaid trough for evacuating whatever gold amalgam that is formed, and astopcock associated with said last-mentioned means, the said stopcockbeing opened at an extent whereby there can be evacuated in a continuousmanner a quantity of amalgam substantially equal to the average quantityof amalgam which is produced.

5. Apparatus for extracting precious metals from ores in a container byamalgamation, comprising a plurality of troughs disposed side by' sidein tandem, each trough containing a filling of mercury, a shaft in eachtrough, means for imparting a continuous rotational movement to saidshafts, a drum mounted on each shaft and adapted to be partiallyimmersed in its corresponding mercury bath, a plurality of circularplates disposed about and concentric with the drum, the said platesextending perpendicularly to the axis of said drum, the said drum andplates being formed of a material not wetted by the mercury, the platesof one of the drums extending between the plates of the neighboringdrum, and means for feeding the ores between the first drum, the platesthereof, and its trough, from the side of the said drum, the platespenetrating into the mercury baths.

6. Apparatus for extracting precious metals from ores in a container byamalgamation, comprising a plurality of troughs disposed side by side intandem, each trough containing a filling of mercury, a shaft in eachtrough, means for imparting a continuous rotational movement to saidshafts, a drum mounted on each shaft and adapted to be partiallyimmersed in its corresponding mercury bath, a plurality of circularplates disposed about and concentric with the drum, the said platesextending perpendicularly to the axis of said drum, the said drum andplates being formed of a material not wetted by the mercury, the platesof one of the drums extending between the plates of the neighboringdrum, means for feeding the ores between the first drum, the platesthereof, and its trough, from the side of the said drum, the platespenetrating into the mercury baths, means disposed at the bottom of eachtrough for removing whatever gold amalgams that are formed, and conduitsinterconnecting the said last-mentioned means at a common point.

7. Apparatus for extracting precious metals from ores in a container byamalgamation, comprising at least one trough filled with mercury, ashaft, means for rotating said shaft continuously, a drum mounted onsaid shaft so as to be partially immersed in the mercury bath, bladesfixed on said drum and disposed in planes perpendicular to the axis ofsaid drum, the said drum and the said blades being formed of a materialwhich is not wetted by mercury, means for feeding the ores between thedrum, the blades, and the trough from the side of the drum, and theblades penetrating into the mercury bath, means for supplying freshmercury to said trough, and an overflow means for removing, outside ofthe trough, materials riding on the surface of the mercury bath.

8. Apparatus for extracting precious metals from ores in a container byamalgamation, comprising at least one trough filled with mercury, ashaft, means for rotating said shaft continuously, a drum mounted onsaid shaft so as to be partially immersed in the mercury bath, bladesfixed on said drum and disposed in planes perpendicular to the axis ofsaid drum, the said drum, and the said blades being formed of a materialwhich is not wetted by mercury, means for feeding the ores between thedrum, the blades, and the trough from the side of the drum, and theblades penetrating into the mercury bath, means for supplying freshmercury to said trough, and an overflow means for removing from thetrough the spent mercury and any silver amalgam which may be formed.

9. Apparatus for the extraction of precious metals from ores byamalgamation, comprising a trough filled with mercury, a shaft, meansfor turning said shaft in continuous manner, blades solid with saidshaft and disposed perpendicularly thereto, and means for introducingthe ore into the trough from that side of the principal axis of thetrough on which the said blades penetrate into the bath of mercury, thesaid shaft and blades being formed of a material which is not wetted bymercury.

CLAUDE JOSEPH FRANCOIS PHILY, nrr nr. PI-IILY.

